Gender-related differences in functional assessment of serotonergic system in healthy young subjects

Introduction. Prolactin stimulation test with serotonergic stimulants has been widely used in the study of diverse psychiatrie disorders. However, the charaeterization of this response in normal subjects is still incomplete. Objective. To compare the response to serotonin stimulation using dexfenfluramine, a specific serotonergic agent, in young healthy men and women, controlling the menstrual cycle. Methods. A total of 10 women and 9 men, who were given 30 mg of dexfenfluramine orally, were studied and their levels of prolactin were measured on an hourly basis for a five-hour period. Baseline, maximum and delta values of prolactin were compared for both groups. Results. According to the age groups studied (mean age for men: 19.9±2.5 years old; mean age for women: 20± 1.5 years old), the prolactin maximum level and the response to prolactin (ΔPRL) were significantly higher in women (p-values: 0.02 and 0.04, respectively). Conclusion. Young healthy women show a greater response to stimulation with dexfenfluramine than young healthy men. Clinical and biological implications of this observaron are discussed in the context of the currently available research papers.